I think the iPad is one vector. I think the social networks you mention are another. That also feels to me like a closing down, or a narrowing. I think Facebook, to take the biggest example, restricts and narrows and makes shallow our communication.[0] It reduces our interactions to shallow, superficial comments, likes, low-fidelity photos, etc. In its way, I think the move toward closed social networks is also a step backward from the open exchange of ideas that blogging represented. And I think this is partially due to the tools we've made, too.

[0]: I wrote more on that here: http://blog.byjoemoon.com/post/3112676038/the-end-of-comment... which was a response to an essay by Zadie Smith.[1]

[1]:http://www.nybooks.com/articles/archives/2010/nov/25/generat...